Acoustic diaphragm



June 17, 1930. 5, w HATTQN 1,763,780

ACOUSTIC DIAPHRAGM Filed June 18 1926 Inventor Tamale? Wflsizon Attorney Patented June 17, 1930 PATENT orrlcs BAIUEL W. HATTON, OF VILLA PARK, NEW YORK ACOUSTIC DIAPHRAGM Application filed June 18,

This invention relates to improvements in acoustic diaphragms particularly for use in connection with sound reproducing apparatus.

The invention has for its primary object ,to provide a diaphragm structure in which I I Y resiliency is materially increased in order to .6 plication:

Figure 1 is an elevational view of one side "of the diaphragm,

Fi re 2 is-a similar view of the opposite sidet ereof, Figure 3 is an edge elevation of the dia- Phmgm.

Figure 4 is a drametncal sectional view taken on a line 4-4 of Figure 1, showing the diaphragm in a partially completed condition so an Figure 5 is a section similar to Figure 4 showm the completed diaphragm structure in whic oneface has been ground ofi to pro-- vide a smooth surface. p I In constructing the diaphragm forming the subjectmatter of this invention, an annealed sheet of iron or other material found "suitable for the purpose is provided in the form of a disk, or if desired may be made 1n other sha than an annular form, and of a site foun most suitable forthe use which ,it' is to be placed. The diaphragm is then A Y placed in an anvil or other support and one surface thereof hammered. The diaphragm is indicated generally, at 1 in the drawings and in Figure 4 the hammer marks provided in the diaphra are illus- -trated lit-2 as forming slight in entations or concavitiesfin one surface of the material. so? In forming these hammer marks it will be 1828. Serial R0. 116,899.

understood that the molecules of the material forming the diaphragm are substantially contracted or compressed throughout the area of the hammer marks.

While the diaphragm may be hammered to produce the indentat1ons shown at 3 in Figure 1, it is understood that any other suitable means known in the art for carrying out the same purpose may be used with equal facility, such as by placing the diaphragm in a die press or the like in which the indentations are formed at apluralitv of points in regular order orin irregular order, as found most desirable, the indentation covering the surface of the diaphragm or any portion of its 55 surface.

The pressure exerted upon the diaphragm during'the hammering or other process forming the indentations on one face thereof changes its shape slightly so that it will be of 7 slightly concavo-convex form throughout the compressed section thereof. This formation also increases the tension and resiliency of the diaphragm and imparts equalities to the material which make it resonant to a wide range of sound wave frequencies.

After the diaphragm is provided with the hammer marks at points of variable compression, as above described, the hammered or compressed surface thereof as shown in F igure 4 is ground to remove the projection or irregularities caused by the hammer marks so I as to provide a completed diaphragm structure of conoavo-convex formation in which both surfaces are smooth, but in which mo- 5 lecular compression of variable or increased density is maintained in the body of the diaphragm.

The diaphragm in itself is considerably more resilient than beforethe hammer treatment and as a resultit is resonant to a wide range of sound frequencies'within the audible on and will reproduce audible sound in a 'ghiy eificient manner and with natural tone reproduction.

It is obvious that 'my invention is susceptible to various changes and modifications in construction without de arting from the spirit of the invention'or e soopeof the oppended claims ,and I. accordingly claim all no.

such forms of the device to which I am entitled.

I claim: 1. An acoustic diaphragm of concavo-con- 5 vex form having a plurality of regions of the material constructed of variable density for increasing resiliency of the diaphragm.

2. An acoustic diaphragm of concavo-convex form having smooth surfaces and provid- 10 ed with regions of increased density in its body for increasing the resiliency of the diaphragm.

In testimony whereof I affix myvsignature.

SAMUEL W. HATTON. 

